Propoxycarbazone-sodium (Ref: MKH 6561)

Propoxycarbazone-sodium (Ref: MKH 6561)	Last updated: 22/08/2024
(Also known as: propoxycarbazone; procarbazone-sodium; BAY MKH 6561)

SUMMARY

Propoxycarbazone-sodium is a post-emergence trazolone herbicide. It is highly soluble in water and mobile in soils and so has a high tendency to leach to groundwater. It is semi-volatile and is not persistent in soil. However, it is persistent in aquatic systems. It has a low oral toxicity and there are no serious human health risks reported. It is moderately toxic to birds, earthworms and fish. Its toxicity to honeybees is low.

Data alerts

The following alerts are based on the data in the tables below. An absence of an alert does not imply the substance has no implications for human health, biodiversity or the environment but just that we do not have the data to form a judgement.

Environmental fate	Ecotoxicity	Human health
Environmental fate High alert: Drainflow: Mobile	Ecotoxicity Moderate alert: Birds chronic ecotoxicity: Moderate; Fish acute ecotoxicity: Moderate; Earthworms chronic ecotoxicity: Moderate	Human health Low alert

GENERAL INFORMATION

Description

A residual herbicide for grass and some broad-leaved weeds mainly in wheat

Example pests controlled

Bromus weeds including cheatgrass, downy brome; Silky-bent; Canary grass; Goatgrass; Wild oats

Example applications

Winter, Spring and Durum wheat; Triticale

Efficacy & activity

Availability status

Current

Introduction & key dates

circa 2000, introduced

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/08/2032

GB LERAP status

Check label - may vary with formulation

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Sweden/Estonia

Date EC 1107/2009 inclusion expires

31/08/2032

EU Candidate for substitution (CfS)

Yes - two 'Persistent-Bioaccumulative-Toxic' criteria

Listed in EU database

Yes

Approved for use (✓) under EC 1107/2009 in the following EU Member States

ATAustria	BEBelgium	BGBulgaria	CYCyprus	CZCzech Republic	DEGermany	DKDenmark	EEEstonia	ELGreece
	✓	✓	✓	✓	✓		✓	✓
ESSpain	FIFinland	FRFrance	HRCroatia	HUHungary	IEIreland	ITItaly	LTLithuania	LULuxembourg
✓	✓	✓			✓			✓
LVLatvia	MTMalta	NLNetherlands	PLPoland	PTPortugal	RORomania	SESweden	SISlovenia	SKSlovakia
✓			✓	✓	✓	✓

Approved for use (✓) under EC 1107/2009 by Mutual Recognition of Authorisation and/or national regulations in the following EEA countries

ISIceland	NONorway

Additional information

Also used in

Chemical structure

Isomerism

Isomeric

Chemical formula

C₁₅H₁₇N₄NaO₇S

Canonical SMILES

CCCOC1=NN(C(=O)N1C)C(=NS(=O)(=O)C2=CC=CC=C2C(=O)OC)[O-].[Na+]

Isomeric SMILES

CCCOC1=NN(C(=O)N1C)/C(=N/S(=O)(=O)C2=CC=CC=C2C(=O)OC)/[O-].[Na+]

International Chemical Identifier key (InChIKey)

JRQGDDUXDKCWRF-UHFFFAOYSA-M

International Chemical Identifier (InChI)

InChI=1S/C15H18N4O7S.Na/c1-4-9-26-14-16-19(15(22)18(14)2)13(21)17-27(23,24)11-8-6-5-7-10(11)12(20)25-3;/h5-8H,4,9H2,1-3H3,(H,17,21);/q;+1/p-1

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide

Substance groups

Triazolone herbicide

Minimum active substance purity

960 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Absorbed by leaves and roots and translocated. Inhibits plant amino acid synthesis - acetohydroxyacid synthase AHAS.

CAS RN

181274-15-7

EC number

605-920-1

CIPAC number

655

US EPA chemical code

122019

PubChem CID

12056759

CLP index number

011-007-00-3

Molecular mass

420.37

PIN (Preferred Identification Name)

IUPAC name

sodium 4,5-dihydro-N-{[2-(methoxycarbonyl)phenyl]sulfonyl}-4-methyl-5-oxo-3-propoxy-1H-1,2,4-triazole-1-carboximidate

CAS name

benzoic acid, 2-[[[4,5-dihydro-4-methyl-5-oxo-3-propoxy-1H-1,2,4-triazol-1-yl)carbonyl]amino] sulfonyl]-, methyl ester, sodium salt

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Herbicide Resistance Class (WSSA MoA class)

Insecticide Resistance Class (IRAC MoA class)

Not applicable

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Physical state

Granular solid

Related substances & organisms

propoxycarbazone

Formulations

Property

Value

Example manufacturers & suppliers of products using this active now or historically

Bayer CropScience

Example products using this active

Attribut
Olympus

Formulation and application details

Often supplied as water soluble granules that are mixed with water and used as a spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C (mg l⁻¹)

42000

High

Solubility - In organic solvents at 20 °C (mg l⁻¹)

100

n-Heptane

100

Xylene

500

Acetone

1500

Dichloromethane

Melting point (°C)

230

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

230

Flashpoint (°C)

Octanol-water partition coefficient at pH 7, 20 °C

2.82 X 10^-02

Calculated

Log P

-1.55

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data

Density (g ml⁻¹)

1.42

Dissociation constant pKa) at 25 °C

2.1

Strong acid

Vapour pressure at 20 °C (mPa)

1.00 X 10^-05

Low volatility

Henry's law constant at 25 °C (Pa m³ mol⁻¹)

1.00 X 10^-10

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

Negligible

24 hr

From soil surface

24 hr

Volatilisation is not considered critical for air pollution

Maximum UV-vis absorption L mol⁻¹ cm⁻¹

pH 6.3: 230nm=12235
pH 12.2: 230nm=14185
pH 1.0: 230nm=140000

Surface tension (mN m⁻¹)

59.0

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

39.6

Moderately persistent

DT₅₀ (lab at 20 °C)

39.6

Moderately persistent

DT₅₀ (field)

5.5

Non-persistent

DT₉₀ (lab at 20 °C)

236.8

Persistent

DT₉₀ (field)

21.6

DT₅₀ modelling endpoint

Note

EU dossier (2015 RAR) Lab studies DT₅₀ range 7.8-215 days, DT₉₀ 65-715 days; Field studies DT₅₀ range 3.4-9.6 days, DT₉₀ range 11.4-31.9 days, Soils=4

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

Note

Aqueous photolysis DT₅₀ (days) at pH 7

Value

18.1

Slow

Note

Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7

Value

9.7

Non-persistent

Note

Stable pH 4 to pH 9 at 25 °C

Water-sediment DT₅₀ (days)

100.5

Slow

Water phase only DT₅₀ (days)

50.7

Stable

Sediment phase only DT₅₀ (days)

Air degradation

As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.

Decay in stored produce DT₅₀

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

Mobile

K_oc (mL g⁻¹)

28.8

Notes and range

EU dossier K_oc range 12.9-106.2 mL g⁻¹

Freundlich

K_f (mL g⁻¹)

0.521

Mobile

K_foc (mL g⁻¹)

32.1

¹/_n

0.935

Notes and range

EU dossier kf range 0.194-1.71 mL g⁻¹, K_foc range 12.9-106.2 mL g⁻¹, ¹/_n range 0.905-0.954, Soils=7

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.85

Calculated

Transition state

SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate

Value

4.71 X 10^-03

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Mobile

Calculated

Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk

13.6

Calculated using the Atkinson method. Assumed 0.5E+06 OH/cm³, 24 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

No data

Known soil metabolites

Metabolite

Major/Minor fraction

$Click here for further information on Major/Minor fraction$

Estimated maximum occurrence fraction

Notes

MKH 6561-N-methyl propoxy triazolinone amide

Major fraction

0.132

MKH 6561-N-methyl propoxy triazolinone

Major fraction

0.343

4-methoxy-1,2-benzothiazol-3(2H)-one, 1,1 dioxide

Major fraction

0.171

propoxycarbazone

Major fraction

methyl 2-sulfamoylbenzoate (Ref: IN D5803)

Major fraction

0.209

1,2-benzisothiazol-3(2H)-one,1,1-dioxide (Ref: IN 00581)

Major fraction

0.267

4-hydroxy-1,2-benzisothiazol-3(2H)-one 1,1-dioxide (Ref: KTS 9357)

Major fraction

0.219

Known groundwater metabolites

Metabolite

EC SANCO/221/2000 relevancy

ADI (mg kg⁻¹ bodyweight day⁻¹)

WHO drinking water guidance value (μg L⁻¹ day⁻¹)

1,2-benzisothiazol-3(2H)-one,1,1-dioxide (Ref: IN 00581)

Not relevant

4-methyl-5-propoxy-2,4-dihydo-3H-1,2,4-triazol-3-one

Not relevant

4-methoxy-1,2-benzothiazol-3(2H)-one, 1,1 dioxide

Not relevant

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

MKH 6561-2-hydroxypropoxy propoxycarbazone (Ref: MKH 6561 M01)
Note: LD50(oral, rat) = 5000 mg/kg bw

Plant

2-sulfamoylbenzoic acid (Ref: MKH 6561 M06)

Animal; Water; Sediment

MKH 6561-carboxylic acid (Ref: MKH 6561 M04; MKH 7018)

Water; Sediment

2-hydroxy-N-methyl propoxy triazolinone (Ref: MKH 6561 M02)

methyl 2-(((5-oxo-3-propoxy-4,5-dihydro-1H-1,2,4-triazol-1-yl)carbonyl)sulfamoyl)benzoate (Ref: MKH 6561 M03)

methyl 2-sulfamoylbenzoate + serine (Ref: MKH 6561 M12)

MKH 6561-N-methyl propoxy triazolinone (Ref: MKH 6561 M10)

a = Water (Hydrolysis); b = Sediment

a = 0.136

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 2000

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

> 1231

Unknown species Reproductive NOAEL

Low

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 10000 mg kg feed⁻¹

Colinus virginianus

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

Colinus virginianus NOEL

Moderate

Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)

> 1000

Eisenia foetida

Low

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

1.25

Eisenia foetida

Moderate

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect
Carbon mineralisation: No significant adverse effect

Dose: 0.035 kg ha⁻¹

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

500.0

Folsomia candida

Non-target plants

1.55

Brassica rapa
Seedling emergence, ED50
as g ha⁻¹

1.55

Brassica rapa
Vegetative vigour, ER₅₀
as g ha⁻¹

Honeybees (Apis spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

> 200

Apis mellifera

Low

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

> 319

Apis mellifera

Low

Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Chronic as 10-day LDD₅₀ µg bee⁻¹ day⁻¹

> 47.6

Apis mellifera

Notes

Bumblebees (Bombus spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Mason bees (Osmia spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Other bee species (1)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Other bee species (2)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Beneficial insects (Ladybirds)

Beneficial insects (Lacewings)

Beneficial insects (Parasitic wasps) as Mortality LR₅₀ g ha⁻¹

Aphidius rhopalosiphi Adult

Beneficial insects (Predatory mites) as Mortality LR₅₀ g ha⁻¹

140

Typhlodromus pyri

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

> 77.2

Oncorhynchus mykiss

Moderate

Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)

107

Pimephales promelas

Low

Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

6.53

Danio rerio EC₅₀ Embryo

Moderate

Temperate Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

> 107

Daphnia magna

Low

Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)

13.8

Daphnia magna

Low

Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)

Aquatic plants - Acute 7 day EC₅₀, biomass (mg l⁻¹)

0.0064

Lemna gibba

High

Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)

1.57

Raphidocelis subcapitata

Moderate

Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)

0.53

Unknown species

Moderate

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves

HUMAN HEALTH AND PROTECTION

General

Property

Value

Source; quality score; and other information

Interpretation

Threshold of Toxicological Concern (Cramer Class)

High (class III)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 2000

Rat

Low

Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)

5000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 5.03

Rat

Other Mammal toxicity endpoints

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

0.4

Rat as propoxycarbazone

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

None allocated

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

0.3

Rat as propoxycarbazone

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks to bystanders or residents identified

Occupational

No unacceptable risks to operators or other workers identified

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

Mammalian dose elimination route and rate

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Possible kidney or adrenals toxicant
Long term effects include weight loss, increased urine pH

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 9
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Environment: H400, H410

WHO Classification

Not listed (Not listed)

UN Number

UN3077

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

propoxycarbazone-sodium

French

propoxycarbazone-sodium

German

Propoxycarbazone-Natrium

Danish

propoxycarbazon-natrium

Italian

propoxycarbazone-sodio

Spanish

propoxicarbazona-sodica

Greek

Polish

propoksykarbazon sodu

Swedish

propoxikarbazonnatrium

Hungarian

Dutch

Norwegian

Record last updated:	22/08/2024
Contact:	aeru@herts.ac.uk
Please cite as:	Lewis, K.A., Tzilivakis, J., Warner, D. and Green, A. (2016) An international database for pesticide risk assessments and management. Human and Ecological Risk Assessment: An International Journal, 22(4), 1050-1064. DOI: 10.1080/10807039.2015.1133242